Automatic damper



Feb. 21, 192s. 1,659,875

.,L. L. JACOBS AUTOMATICv DAMPER Filed Sept, 22. 1926 Patented Febf 2l, A19218.

UNITED STATES LIONEL IIJ. JACOBS, OF TORONTO, ONTARIO,

,t 1,659,875 PATENT f OFFICE.

CANADA.

AUTOMATIC DAMrim Application filed September 22, 1926. Serial No. 137,074.

of an adjustable stop for the damper whichmay be adjusted from without to limit the p movement of the damper in closing."

In the drawings, Figure 1 isa perspective view showing the arrangement in a length of pipe. f Fi e 2 is a vertical mid-sectional view showing the arrangement of the thermostatic spring and adjustable stop member.

V'] .`hermostatically controlled dampers of various forms have been proposed but local conditions require adjustments being made p to suit the existing conditions and the presentinvention proposes in a simple manner to accomplish this'result by providing a damper which may be set to an adjustment to satisfactorily automatically control the re. In the form of the invention shown, the pipe 1 which may bef'of any desired size has arranged therein a ring 2 which may be of cast metal and fits snugly against the inner wall of the pipe and may be secured in place by ts.

rive A li ht shaft 3 extends diametrically acro t e ring.2 and the `end 4 thereof extends through a bearing inthe ring and projects outwardly beyond the wall of ythe pipe 1.

The damper member 5 of a suitable diameter is arranged below the shaft 3 and a lug 6 extends u wardly from the damper at one side thereo the end 4 of the rod passing through the lug and pivotally supporting the damper at one side. r Mounted on the opposite side of the damper member 5 isa block 7 having a lug projection 8 which is drilled through from its mward side and loosely encircles the free end of the shaft 3. Extending outwardly fromthe block 7 and in axial the shaft 3 and forming part a sleeve 9, The sleeve 9 passes of the'block is through the of the device alignment with tion relative to the flue temperature.

ring 2and is rotatable a short distance outwardly beyond the outer wall of the pi e 1`where it may be provided with a suitab e pointer 10 which will indicate the position of the damper member within the pipe.

A spirally sha ed thermostat member 11 encircles the sha midway of itsl length, the inner end thereof being rigidly secured to the shaft in 'any desired manner. The" thermostat member 11 is formed from a .length of the usual composite material having its wall formed of two layers of metal each having a diierent co-eicient of exanslon.

An openin ber 5l centra y thereof to accommodate the 12 is cut in thedamper memtherein and extends lower extremity ofithe thermostatic member 11 and the free end 13- of the thermostat extends towards the outer edge ofthe damper member 5 and is rigidly securedthereto.

Secured to the pipe'l is a member 14 having an annular flange 15 encircling the projecting end 4 of the shaft, the flange 15 being rovided witha number of op ositely arranged holes 16 which extend rad) through'. A hole 17 is drilled through the end 4 of the shaft and a in 18 is passed therethrough andv through t e holes 16,. thus' locking the shaft in any desired position.

Threaded in a boss 19 mounted on the ipe 1 is an adjustable sstop 2O which is adapted to-extend inwardly below the adjacent side of the damper member 5 to engage the same to limit its movement in the closed ially theredirection. The inward end of the stop 2O is not threaded.

' A cap 21 ma be threaded into the boss 10 and encloses t e outer end .of the stop 20 thus preventing the member 2O from being tampered with when the proper setting has been obtained.

The device is so set that' when there is no re burning in the furnace the vdam er member 5 will be in a position longitu inally of the pipe 1, this position being determlned by the pin 18 passing through the hole 17 in the shaft.

Upon the fire being lighted, the hot gases passin through the pipe 1 come in contact with t e thermostat member 1l and as the temperature expands spirally and gradually turns theI damper on its pivot until it assumes a prsiof the member 1l increases it damper thus automatically retains a draft opening proportional tothe intensity of thc If for any reason the fire should become so hot as to cause the damper to rotate past its normal position, the stop is provided to limit its movement so that the iue'passage cannot be cut down to too small an area and cause noxious gases to be discharged into the furnace room 0r cause vsuch an accumulation of unburnt gases which might result in an explosion.

' A device such as described will be applicable to stoves or furnaces of various types and Will be extremely efficient inits function lof lpreventing the gases of combustion being drawn too rapidly through the furnace over the heating surfaces.

It will be readily appreciated by those skilled in the art that iue conditions vary to a very marked degree due to size, construction and location as well as to the differences in furnace equipment and it is very important that an automatic damper must be capable of adjustment to meet these conditions vas well as to account for variation in the physical structure of the dampers. The present invention having the thermost -atic spring adjustable and also being proto meet the required conditions'.

What I claim as my invention is l. An automatic damper comprising, the combination `with the flue pipe, secured to the inner periphery of said pipe and having a bearing extending therethrough, a damper plate disposed within said ring having a trunnion supported in said bearing, a shaft rotatably mounted in said ring and pivotally supporting said damper plateat the side opposite said trunnion and having one vend extending outwardly beyond the wall of said pipe, a coiled thermostatic spring encircling said shaft having one end secured thereto and the other end connected with said damper4 plate, and means secured to said flue pipe engaging the extending end of the shaft for locking the same in various adjusted positions.

j 2. An automatic damper comprising, the

vlded with an adjustable stop has been found .A

of a ringl wardly therebeyond, a boss mounted on said flue pipe having an annular flange encircling said projecting end of the shaft, radially disposed holes arranged in said annular flange, a hole in the projecting end of said' shaft in alignment with the aforesaid holes, a. removable pin passing through the aligned holes and adjustably locking said shaft in a fixed position, a damper plate pivotally susa pcnded from said shaft, a thermostatic spring secured to the shaft and having its free end connected with said damper plate,

and means for limiting the movement of said damper plate in the -closed direction.

8. An automatic damper comprising, the combination with the flue pipe, of a shaft mounted in saidv flue extending'transversely thereof, a damper plate arranged below said shaft and having a lug extending upwardly atone sidethereof pivotally supported on said shaft, a bearing member secured to the other side of said damper member and being drilled to receive the end of said shaft and having a Lcylindrical` portion extending outwardly therefrom through the wall of said flue pipe concentric with said shaft, anindicator secured to the outward end of vsaid cylindrical portion, a thermostatic spring secured to and encircling said shaft and operatively connected with said damper plate, and means for locking said shaft in various adjusted positions.

4. An automatic damper comprising, thc combination with the flue, of a damper pivotally suspended within said fluo, a thermostatic spring arranged within said-flu(` having one end adjustably fixed with relation to the flue and having thel other end operatively connected with said damper, a threaded boss extending from the wall of said flue, a rod threaded into said boss from the inner side and adapted to engage said damper to limit its degree of closing, and a cap member threaded into said Iboss and enclosing the outward end of said stop member.

LIONEL L. lIAooBs. 

